Here "hands" and "fingers" refers to their actions. This means they are guilty of doing violent and sinful things. "Your" is plural. Alternate translation: "For you have committed violent sins" (See: [[rc://en/ta/man/translate/figs-metonymy]] and [[rc://en/ta/man/translate/figs-you]])
The parts of the body that make speech represent what people say. Alternate translation: "You speak lies and malicious things" (See: [[rc://en/ta/man/translate/figs-metonymy]])